Search rows having matching sub text in the middle of a cell text in Power Apps

I'm making a power app for searching matching sub text rows in a Sharepoint table column. I've found the functions for searching rows that starts- or ends- with the search string (see my formula below), but simply not able to find the corresponding function for finding sub text that is in the middle of the row cell. E.g. if I'm looking for rows that have the search string 'cat' I would like the filter function to return rows that contains 'dogs and cats', but currently my function does not manage to do that. It only returns a row if it starts with or ends with 'cat', like this: 'cats and dogs'.

Here is my filter function:

SortByColumns(
    Filter(
        [@'myTable']; 
        StartsWith(Title; Text(mySearchTextBox.Text)) || EndsWith(Title; Text(mySearchTextBox.Text))
    )
    ; "Title"
    ; If(SortDescending1; Descending; Ascending)
)